Tutorial to Fix Firefox Profile Missing Error

What is Mozilla Firefox profile?

In Mozilla Firefox, all of your personal information includes your bookmarks, history, passwords, toolbar settings, are saved in a file named profile. By default, the Firefox profile is separated from installation program. Whether you uninstall Firefox or virus aggressive Firefox browser, your private information will stay on your computer safely. Each time you launch Firefox, it always read the content of profile first.

Why can Firefox not load profile?

According to the error of the profile cannot be loaded, here are three reasons in total:

Firefox profile has been deleted

Firefox profile has been transferred

Firefox profile has been renamed

We provided different solution below according to different situation. Let's move on to learn the detail.